/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

// This fetcher routes requests to hosts that are not explicitly mentioned in
// the DomainLawyer towards our own IP, as extracted from the incoming
// connection.

#ifndef PAGESPEED_SYSTEM_LOOPBACK_ROUTE_FETCHER_H_
#define PAGESPEED_SYSTEM_LOOPBACK_ROUTE_FETCHER_H_

#include "net/instaweb/http/public/url_async_fetcher.h"
#include "pagespeed/kernel/base/basictypes.h"
#include "pagespeed/kernel/base/string.h"

struct apr_sockaddr_t;

namespace net_instaweb {

class AsyncFetch;
class RewriteOptions;
class MessageHandler;

// See file comment.
class LoopbackRouteFetcher : public UrlAsyncFetcher {
 public:
  // Does not take ownership of anything. own_port is the port the incoming
  // request came in on, and own_ip is the same for the IP. If the
  // backend_fetcher does actual fetching (and is not merely simulating it for
  // testing purposes) it should be the Serf fetcher, as others may not direct
  // requests this class produces properly.
  // (As this fetcher may produce requests that need to connect to some IP
  //  but have a Host: and URL from somewhere else).
  LoopbackRouteFetcher(const RewriteOptions* options,
                       const GoogleString& own_ip, int own_port,
                       UrlAsyncFetcher* backend_fetcher);
  ~LoopbackRouteFetcher() override;

  bool SupportsHttps() const override {
    return backend_fetcher_->SupportsHttps();
  }

  void Fetch(const GoogleString& url, MessageHandler* message_handler,
             AsyncFetch* fetch) override;

  // Returns true if the given address is an IPv4 or IPv6 loopback.
  static bool IsLoopbackAddr(const apr_sockaddr_t* addr);

 private:
  const RewriteOptions* const options_;
  GoogleString own_ip_;
  int own_port_;
  UrlAsyncFetcher* const backend_fetcher_;

  DISALLOW_COPY_AND_ASSIGN(LoopbackRouteFetcher);
};

}  // namespace net_instaweb

#endif  // PAGESPEED_SYSTEM_LOOPBACK_ROUTE_FETCHER_H_
